My digitizer (old one calcomp model no 34480) is not working well I hope I had change the switch on the PCB while wiping. Will you please help me which number switch should be on?

SOURCE: Hi I have an Calcomp Drawing

You can get accessories from www.gtcocalcomp.com for your DB3.
Also try calling 1-800-digipad

SOURCE: GTCO CalComp Drawing Board III

First conform that serial port is selected as NONE on digitizer manager while you running the lectra tablet utilities. If you try this already please check your cable connectivity any one of the line may be missing connection. It may work but you can't able to run lectra tablet utilities.